Rendered result has single color, instead of cine in viewport

[left crane]

I was working on a shape made in geometry nodes, with particle grass and quite some lights (see pic 1.). I finished shading everything, animated the camera movement and I wanted to render out a frame. it worked like 2 times (see pic 2. - cycles render), but then suddenly render started showing single color. in eevee the color is grey (same as world settings) and in cycles it is bright yellow (same as color of one plane that I put above camera with emission to light up the scene a bit).
I've managed to somehow get rid of it for one render, but then as suddenly it got solved, It got broken again. Because I was trying to fix this issue for last 4 hours I tried fixing it in various ways and so i dont really remember what fixed it before. All I remember is that I was changing something with world shading, color settings in render tab and I've tried compositing the working rendered image.
Although the viewport from camera perspective shows it like i want it to (see pic 5.) It renders it wrong.
Thank you for any tips how to resolve this:')

[maiden kayak]

Hi @left crane !

i have a few ideas that may solve this issue

1st: Now i doubt this is the problem but you said you were changing the world shading. I have just made a small scene as an example and if you turn the STRENGTH up in the world colour you can overide your lights and get a blank colour, this doesnt seem the case though because your viewport display is fine, but it may be worth a look.

2nd: May you have any lights or objects that are hidden in the viewport but are visible in the final render?

[maiden kayak]

3rd: Your blank render image is coming up as a 'Composite'. This happens when you have edited with the compositor as you said you had. Check in Layer Properties Panel to make sure you didn't tick a pass, for example like a cyrptomat. Also copy and then delete your compositing and only use the default node set up (the render layer and the output composite). This will show if there is any problem happening in the compositor. Hope this helps, amazing creation by the way!

4th: Here "i by accidentally" added a colour pass and it has made my render into blobs of colour without any shadow or depth. If you click on the Composite button (grey box with an arrow on the top right hand corner of your rendered image) and select View Layer, you can select different layers. Select Combined to see the original output by blender without any extra compositing or passes. This will let you know if your problem comes from compositing or as a raw output from the camera.